1. Field of the Invention
The present invention relates to a thermal storage type gas treating apparatus comprising a plurality of thermal storage chambers containing a thermal storage medium, each of the thermal storage chambers having one end thereof communicating with a combustion chamber having a combustion device; a valve member disposed between a distributor and a gas chamber device to be rotatable in slidable contact with the distributor and the gas chamber device, the distributor defining a plurality of supply and exhaust ports arranged in a direction of rotation of the valve member, each of the supply and exhaust ports communicating with the other end of one of the thermal storage chambers; the valve member defining a supply port for a gas to be treated and an exhaust port for a treated gas arranged to oppose to and communicate with said supply and exhaust ports, with rotation of the valve member, the supply port and the exhaust port not opposing to or communicating with the same supply and exhaust ports simultaneously; a gas feed passage for communicating with the supply port in the valve member through the gas chamber device, and a gas exhaust passage for communicating with the exhaust port of the valve member through the gas chamber device; and a distributor-side seal element disposed between the distributor and the valve member for precluding communication between the supply port and the exhaust port through a gap between the distributor and the valve member; the valve member being rotatable to supply the gas to be treated introduced from the gas feed passage into the valve member to the distributor through the supply port, and to discharge the treated gas exhausted from the distributor to the valve member through the exhaust port to the gas exhaust passage.
The present invention also relates to a seal structure and a resistance adjusting mechanism of a rotation type selector valve usable with the thermal storage type gas treating apparatus.
Further, the present invention relates to a thermal storage medium layer cleaning method executed for the above thermal storage type gas treating apparatus.
2. Description of Related Art
As a thermal storage type gas treating apparatus of this type, and a rotation type selector valve usable with the thermal storage type gas treating apparatus, the following are known.
(Outline of the Thermal Storage Type Gas Treating Apparatus)
Conventionally, in the thermal storage type gas treating apparatus, a gas to be treated introduced into a valve member from a gas feed passage is passed through a supply port of the valve member and supply and exhaust ports opposed to and communicating with the supply port, and through part of thermal storage chambers to a combustion chamber. In the combustion chamber, contaminants, offensive odor substances and the like in the gas to be treated are disposed of by combustion.
The treated gas is passed through the other thermal storage chambers to store the heat in a thermal storage medium in the thermal storage chambers. Then, the gas is passed through the supply and exhaust ports opposed to the thermal storage chambers, and through an exhaust port of the valve member opposed to and communicating with the supply and exhaust ports, out into a gas exhaust passage.
In this process, the valve member is rotated to switch each of the supply port and exhaust port of the valve member to oppose to and communicate with successively different ones of the supply and exhaust ports (namely, to successively switch the thermal storage chambers for passing the gas to be treated and the thermal storage chambers for passing the treated gas). As a result, the thermal storage medium storing the heat from the treated gas having passed therethrough preheats the gas to be treated passing through each thermal storage chamber, thereby to achieve an improvement in thermal efficiency.
(Biasing Structure for the Seal Portion)
In this type of thermal storage type gas treating apparatus, a seal element (i.e. a distributor-side seal element) precludes communication between the supply port and exhaust port through a gap between a distributor and the valve member. Thus, the gas to be treated passing through the supply port is prevented from mixing into the treated gas discharged from the distributor to the exhaust port of the valve member. A seal element of a gas chamber device prevents the gas from leaking through a gap between the gas chamber device and valve members. As a result, the gas to be treated introduced through the supply port is prevented from mixing into the treated gas exhausted to the exhaust port of the valve member.
Conventionally, for the breaking of communication by the distributor-side seal element (i.e. sealing) between the valve member and distributor, the distributor-side seal element is attached to the distributor as attached to a biasing device such as elastic elements. By pressing the distributor-side seal element toward the valve member with this biasing device, the distributor-side seal element is reliably placed in pressure contact with the valve member. For the breaking of communication by the seal element of the gas chamber device between the valve member and gas chamber device, the seal element is attached to the gas chamber device as attached to a biasing device such as elastic elements. By pressing the seal element of the gas chamber device toward the valve member with this biasing device, the seal element of the gas chamber device is reliably placed in pressure contact with the valve member. A proposal has been made to enhance sealing performance with the two seal elements (see Patent Document 1, for example).
(Seal Structure of the Rotation Type Selector Valve)
The rotation type selector valve noted hereinbefore (see FIG. 36) switches an opposed and communicating relation between a plurality of main valve ports and a plurality of auxiliary valve ports by switching the main valve ports opposed to each auxiliary valve port with a relative rotation between a main valve component and an auxiliary valve component, thereby switching a connecting relation between a plurality of main passages and a plurality of auxiliary passages. Between a main opposite surface of the main valve component and an auxiliary opposite surface of the auxiliary valve component close and opposed thereto, a seal element is disposed for preventing fluids, which should pass through different main valve ports and auxiliary valve ports, from becoming mixed through a gap between the two opposite surfaces.
For attaching this seal element, there are a form in which the seal element attached to the auxiliary opposite surface is placed in slidable contact with the main opposite surface, and a form in which, conversely to the above, the seal element attached to the main opposite surface is placed in slidable contact with the auxiliary opposite surface. In the form of attaching the seal element to the auxiliary opposite surface of the auxiliary valve component, as shown in FIGS. 36 and 37, the seal element attached to the auxiliary opposite surface includes annular seal portions surrounding an axis of relative rotation between the main valve component and auxiliary valve component, and located at opposite outer sides (inside and outside in the illustrated example) in a direction of width of a row of the main valve ports, to be slidable in contact with the main opposite surface at opposite outer sides (also inside and outside in the illustrated example) of a row of the main valve ports, and dividing seal portions located in the middle of closed portions between the adjacent auxiliary valve ports, seen in the direction of the relative rotation, and having a linear shape extending between the two annular seal portions located at the opposite outer sides (inside and outside) in the direction of width of the row of the auxiliary valve ports, to be slidable in contact with the main opposite surface . . . Conventional Example 1 (see Patent Document 2).
In the form of attaching the seal element to the main opposite surface of the main valve component, on the other hand, as shown in FIGS. 39 and 40, the seal element attached to the main opposite surface includes annular seal portions surrounding the axis of relative rotation between the main valve component and auxiliary valve component, and located at opposite outer sides (inside and outside in the illustrated example) in a direction of width of a row of the main valve ports, to be slidable in contact with the auxiliary opposite surface at opposite outer sides (also inside and outside in the illustrated example) of a row of the auxiliary valve ports, and dividing seal portions located adjacent and outside two edges, seen in the direction of the relative rotation, of each of the main valve ports, and having a linear shape extending between the two annular seal portions located at the opposite outer sides (inside and outside) in the direction of width of the row of the main valve ports, to be slidable in contact with the auxiliary opposite surface . . . Conventional Example 2 (see Patent Document 3).
In the form of attaching the seal element to the main opposite surface of the main valve component, a proposal has been made to attach the seal element to the main opposite surface “x” as shown in FIGS. 43 and 44. The seal element includes annular seal portions surrounding the axis of relative rotation between the main valve component and auxiliary valve component, and located at opposite outer sides (inside and outside) in a direction of width of a row of the main valve ports, to be slidable in contact with the auxiliary opposite surface at opposite outer sides (inside and outside) of a row of the auxiliary valve ports, and planar dividing seal portions extending between the annular seal portions, and covering entire surfaces of the respective closed portions Sx between the main valve ports, to be slidable in contact with the auxiliary opposite surface . . . Conventional Example 3 (see Patent Document 4).
(Pressure Adjusting Mechanism of the Rotation Type Selector Valve)
A conventional rotation type selector valve of this type has a valve seat plate, and a rotary valve member rotatable in slidable contact with the valve seat plate. The valve seat plate defines a plurality of selectable passage ports arranged in a direction of rotation of the valve member. The valve member defines a first and a second internal passages each having a selecting side opening at one end thereof for becoming opposed to and communicating with the plurality of selectable passage ports successively with rotation of the valve member, and a common side opening at the other end movable in the direction of rotation of the valve member. The selecting side opening of the first internal passage and the selecting side opening of the second internal passage are arranged not to become opposed to or communicating with the same one of the selectable passage ports simultaneously.
A first passage chamber and a second passage chamber are provided in constant communication with the common side openings of the first and second internal passages movable in the direction of valve rotation with rotation of the valve member. A first common passage port opens into one location in the direction of valve rotation of the first passage chamber. A second common passage port opens into one location in the direction of valve rotation of the second passage chamber. This rotation type selector valve is used, for example as a switching device of the thermal storage type gas treating apparatus (Patent Document 2, for example).
(Gas Cooling Device)
Further, a conventional thermal storage type gas treating apparatus of this type switches, with a switching device, the thermal storage medium layer which passes the gas to be treated to the combustion chamber, and the thermal storage medium layer which passes the treated gas from the combustion chamber. The thermal storage medium storing the heat from the hot treated gas from the combustion chamber having passed therethrough preheats the gas to be treated passing through thermal storage medium in the next step. The preheated gas to be treated is put to combustion treatment in the combustion chamber. This reduces the amount of heating in the combustion chamber required for combustion treatment of the gas to be treated. Conventionally, in this type of thermal storage type gas treating apparatus, the hot treated gas from the combustion chamber having passed through the thermal storage medium layer for thermal storage is discharged as it is through a portion of the gas supply and exhaust gas passage where the switching device is mounted (Patent Documents 4 and 5, for example).
[Patent Document 1] Patent Publication “Kokai” No. 2001-74225
[Patent Document 2] Patent Publication “Kokai” No. H10-61940
[Patent Document 3] Patent Publication “Kokai” No. H7-305824
[Patent Document 4] Patent Publication “Kokai” No. 2001-304531
[Patent Document 5] Patent Publication “Kokai” No. H9-217918
However, the prior art noted above has the following problems.
(Biasing Structure for the Seal Portion)
The construction having the distributor-side seal element attached to the distributor as attached to the biasing device requires a construction that allows the distributor-side seal element alone to move toward and away from the valve member while also maintaining gastightness between the distributor-side seal element and distributor. This poses a problem of complicating the apparatus construction and rendering manufacture of the apparatus difficult.
Since the distributor-side seal element is displaced alone, the displacement tends to be accompanied by clattering. This poses a problem of lowering sealing performance all the more.
Similarly, the construction having the seal element of the gas chamber device attached to the gas chamber device as attached to the biasing device requires a construction that allows the seal element gas chamber device alone to move toward and away from the valve member while also maintaining gastightness between the seal element of the gas chamber device and the distributor. This poses a problem of complicating the apparatus construction and rendering manufacture of the apparatus difficult. Since the seal element of the gas chamber device is displaced alone, the displacement tends to be accompanied by clattering. This poses a problem of lowering sealing performance all the more.
In view of this state of the art, a primary object of the present invention is to solve the above problem effectively with a rational improvement.
(Seal Structure of the Rotation Type Selector Valve)
In the construction having the seal element attached to the auxiliary opposite surface (FIGS. 36 and 37), where the width θd′ in the direction of rotation of the closed portion Sx between the main valve ports in the main opposite surface is equal to or larger than the interval θmn′ between adjacent dividing seal portions (θd′≧θmn′; strictly, equal to or larger than the inside measurement interval between adjacent dividing seal portions) on the auxiliary opposite surface as shown in FIGS. 38 (a) and (b), it is possible to prevent mixing of the fluids which should pass through different main valve ports and auxiliary valve ports. Therefore, the width θn′ in the direction of rotation of the closed portions Sy between the auxiliary valve ports in the auxiliary opposite surface may be made small. As a result, a large width θm′ in the direction of rotation of each auxiliary valve port in the auxiliary opposite surface is secured (in other words, a large opening area of each auxiliary valve port is secured). This is advantageous in reduction of fluid pressure loss and compactness of the apparatus. However, the construction of the Conventional Example 2 of having the seal element attached to the main opposite surface “x” has a problem that the width θm the direction of rotation of each auxiliary valve port in the auxiliary opposite surface “y” is restricted to be small.
That is, in the construction of Conventional Example 2 (FIGS. 39 and 40), to avoid a fluid mixture in the form shown in FIG. 42 (a) and a fluid mixture in the form shown in FIG. 42 (b), as shown in FIG. 41 (a)-(c), the interval θd between adjacent dividing seal portions on the closed portion Sx between the main valve ports in the main opposite surface “x” (in short, the width in the direction of rotation of the closed portion Sx) must be made equal to or larger than the width θm in the direction of rotation of each auxiliary valve port in the auxiliary opposite surface, and the width θn in the direction of rotation of the closed portion between the auxiliary valve ports in the auxiliary opposite surface equal to or larger than the interval θd between adjacent dividing seal portions on the closed portion Sx between the main valve ports in the main opposite surface (θd≧θm and θn≧θd). Therefore, the width θm in the direction of rotation (opening area) of each auxiliary valve port in the auxiliary opposite surface is restricted to be small. A solution of this problem is desired since, in certain situations, such as because of design conditions, the seal element must be attached to the main opposite surface of the main valve component.
In the construction of Conventional Example 3, as shown in FIGS. 45 (a) and (b), as long as the width θd in the direction of rotation of the planar seal portions is equal to or larger than the width θm in the direction of rotation of each auxiliary valve port in the auxiliary opposite surface, it is possible to prevent mixing of the fluids which should pass through different main valve ports and auxiliary valve ports. Therefore, the width θn in the direction of rotation of the closed portions Sy between the auxiliary valve ports in the auxiliary opposite surface may be made small (that is, the width θm (opening area) in the direction of rotation of each auxiliary valve port 16 may be made large). However, the seal element cannot be formed only of linear seal portions. The seal element must have a special shape having planar dividing seal portions of large area equivalent to the closed portions Sx between the main valve ports. This poses problems that the manufacture cost of the seal element is high, an attachment mode of only fitting the linear seal portions in grooves is insufficient, and attachment of the seal element to the main opposite surface also is difficult.
In view of the state of the art noted above, a primary object of the present invention is, in the form of attaching a seal element provided between the main opposite surface and auxiliary opposite surface to the main opposite surface, to secure a large opening area of each auxiliary valve port in the auxiliary opposite surface, while avoiding specialization of the shape of the seal element as in Conventional Example 3, thereby realizing an improved performance of the thermal storage type gas treating apparatus.
(Pressure Adjusting Mechanism)
In the conventional rotation type selector valve described hereinbefore, in the movement of the common side opening of the first internal passage in the direction of rotation of the valve member accompanying a rotation of the rotary valve member, it alternately assumes the position shown in (a) of FIG. 46 having approached the first common passage port and the position shown in (b) of FIG. 46 away from the first common passage port. In the state where the common side opening of the first internal passage has approached the first common passage port, a small fluid passage resistance occurs between these openings. In the state where the common side opening of the first internal passage has moved away from the first common passage port, on the other hand, an increased fluid passage resistance occurs between these openings. The variations in the passage resistance pose a problem of periodic variations in the flow rate of the fluid through the first internal passage (the treated gas in the preceding example of thermal storage type gas treating apparatus) occurring with a rotation of the rotary valve member. There was also a problem of periodic variations in the flow rate of the fluid through the second internal passage (the gas to be treated in the preceding example of thermal storage type gas treating apparatus) occurring for the same reason.
Particularly, in the rotation type selector valve shown in FIG. 46, when the common side opening of the first internal passage has approached the first common passage port, the two openings are adjacent and facially opposed to each other in the first passage chamber. When the common side opening of the first internal passage has moved away from the first common passage port, on the other hand, the two openings communicate with each other through a narrow fluid passage extending circumferentially of the rotary valve member in the first passage chamber. In this valve construction, large variations occur in the fluid passage resistance between the two openings. Therefore, the periodic flow rate variations accompanying a rotation of the rotary valve member are especially notable.
In the thermal storage type gas treating apparatus using this rotation type selector valve, t the periodic flow rate variations of the passing fluid noted above (i.e. volume variations of the passing gas) gives rise to problems of a lowering of apparatus performance and operating trouble.
In view of this state of the art, a primary object of the present invention is to provide a rational improvement for preventing the periodic flow rate variations in the rotation type selector valve, and preventing a lowering of performance and operating trouble of the thermal storage type gas treating apparatus resulting from the periodic flow rate variations.
(Cooling Device)
In the conventional thermal storage type gas treating apparatus, the switching device has seal elements of various constructions in order to prevent mixing of the gas to be treated into the treated gas by leakage, and the leakage to the exterior of each gas. To avoid heat damage of the seal elements, the temperature of the treated gas discharged from the combustion chamber is restricted. Therefore, the temperature of the gas to be treated introduced into apparatus (inlet temperature in the thermal storage type gas treating apparatus) and the combustion temperature in the combustion chamber are also restricted to limit the gas that can be treated. There have been cases where sufficient combustion treatment cannot be performed in the combustion chamber.
In view of this state of the art, a primary object of the present invention is to solve the above problem effectively with a rational improvement.